Improvement in glass-molds



J. H. HOBBS Glass-Molds.

No.-206,fll. Patented July 16, 1878.

N. m PHOTCHJTWMER WASHINGTON. D Q

UNITED STATES PATENT OFFICE.

JOHN H. HOBBS, OF W'HEELING, \VEST VIRGINIA.

IMPROVEMENT IN GLASS-MOLDS.

Specification forming part of Letters Patent N0. 206,] l l, dated July16, 1878; application liled July 1, 1878.

To all whom. it may concern:

Be it known that I, J QHN H. Hones, of Wheeling, county of Ohio, Stateof West Virginia, have invented or discovered a new and usefulImprovement in Glass-Molds; and I do hereby declare the following to bea full, clear, concise, and exact description thereof, reference beinghad to the accompanying drawing, making a part of this specification, inwhich-like letters indicating like parts- Figure 1 is a vertical centralsectional view of my improved glass-mold, taken in the line y y, Fig. 2.Fig. 2 is a transverse sectional View of the mold in the line a; as,Fig. 1; and Fig. 3 is a perspective view of a glass article made in myimproved mold.

My invention relates more particularly to the manufacture of glasslantern-tubes, chimneys, or globes, such as are referred to in PatentNo. 201,072 to Thomas Walton, of March 5, 1878.

Some difficulty has been experienced in the making of such articles,chiefly from the difficulty of devising a mold capable of working theglass into the shape desired with practical success. 1 r

In the drawing, A represents the female part of an ordinarypressing-mold, having a cavity of the exterior form of the article to bemade. The rin g-plate Bis also of the ordinary or any suitableconstruction, except that to it are at tached one or more mandrels, a,of suitable size for forming the tubular elliptical or open passages orair-ducts c in the wall of the article c to be made, and they are soshaped and proportioned as to leave, when in position, a cavitylaterally on all sides, as in Fig. 2, for the making of the glass wallsof the tube, chimney, or globe. The plunger 1) has a correspondingnumber of recesses, 11, in the periphery, each shaped with reference tothe adjacent mandrel a, as last above stated. The plunger, in otherrespects, is of the ordinary construction. Ordinary known appliances areto be added, and, except as herein described, features of constructionand operation are such as are well known in the art of pressing hollowglassware.

It is important, however, in working my inventlon, that the mandrels abe placed substantially in the position they are to occupy while thepressing is being done, before the pressing operation begins, or beforethe heaviest part is reached, so that when such pressing operation isbeing done they shall be comparatively or absolutely stationary, orshall have practically no longitudinal motion, and also shall have afirm end support, preferably at both ends, and particularly at the lowerend. Within these limits the construction and operation of the devicesnamed may be varied at pleasure. Preferably, however, I attach eachmandrel a to the ring-plate B, so that one motion may sufh'ce forputting ring-plate and mandrels in position, and also in removing themafter the pressing is done.

To steady and support the mandrels, so as to prevent undue springing orbending, I seat the lower end of each in a shoe or socket in the bottomof the mold-cavity, or make a dowel-pin connection, as shown at 8. Toinsure getting the mandrels into the right position circumferentially,any suitable guide or index may be employed, registering or otherwise,and index-notches 0, made in the ring-plate and mold, may suffice forthe purpose.

The rin g-plate and mandrels being properly in position, the prop erquantity of melted glass is dropped into the mold, after which theplunger is forced down, the pressing is done, and, by reversing theorder of operation, the article is removed, all in the usual way.

I thus produce a glass globe, tube, or chimney, 0, having one or moreair ducts or passages, c, made longitudinally in its wall, such as arecalled for in the patent above named. The usual finishing operations areto be added, and to a greater or less extent, if desired, according tothe skill of the workman. The article may be brought to the globular orsemiglobular form sometimes desired in chimneys and globes.

I do not limit myself to any particular form of mandrels or way ofgetting them in place. They may be operated by a plunger-like motionthrough the bottom of the mold, and a part of such motion may take placeafter flumain. plunger has commenced its stroke. lint I deem itessential that the lower ends of such mandrels be held securely in placeas against lateral bending or springing at the time the pressing isbeing done by the main plunger,

206. I l l and, preferably, each mandrel should be supported at bothends at such time.

Any desired number of such mandrels, one or more, may be employed.

I claim herein as my invention- 1. In a glass-pressing mold, a mandrelor mandrels, arranged within the moldcavity alongside the path of thepressing-plunger, and firmly held or supported each at its lower end atthe time the heaviest operative pressure is applied, in combination withthe plunger vhigh does the pressing, substantially as set ort 2. Incombination with a pressing-mold and plunger, a ring-plate, carrying oneor more mandrels, which shall be stationary between plunger andmold-face while the pressing is being done, substantially as set forth.

3. One or more stationary mandrels firmly held or supported at both endsin the cavity of a pressing-mold, alongside the path of the plunger, ineombmation with plunger and mold, substantially as set forth.

4. The combination of mold, plunger, mandrels, and guide or index,substantially as set forth.

In testimony whereof I have hereunto set my hand.

JOHN H. HOBBS. Witnesses:

J. J. MCCORMICK, ULAUDIUS L. PARKER.

